Draft gear



Al C. UAVIDSON.

DRAFT GEAR. APPLicATwN FILED MAX/7,1920.

A. C. DAX/DSGN, DRAF? GEAR. ,-ur'pucmzon me@ my me.

itil; s

IN VEN TUR ARTHUR C. DAVIDSON, 0F C-IUGO, LLNlS,

oneri* einen,

Application filed Etsy 7, m2o.

To all ,whom t may concern-f Be it known that l, ARTHUR C. DiivinsoN, a citizen o't' the United States, residing at Chicago, in the county oCook and State of Illinois, have invented a new and useful improvement in Draft Gears, of which the following is a specification.

rihis invention pertains particularly to draft-gears of the type utilizing both spring pressure and friction in the buiiing and pulling operations.

The primary object of the invention is to provide an improved-construction which is strong and durable and which is capable of utilizing, in as high a degree as possible, the compressive action ot' a spring orgsprings and the maximum Jfrictionul 'resistance which can be attained in a device of this character. i

A further object is to provide a simple construction involving few parts, which can be readily assembled.

The invention is illustrated in its preferred embodiment in the amrompanying drawings, in which- F ig. l represents' a broken plan view, partly in section, of the improved draft-gear and the sub-structure ot a car on which same is mounted;l Fig. Q, a central vertical longitudinal sectional view of the same, the,

transverse vertical sectional view taken as indicated at line 5 of Fig. 3.

ln the constriwtion illustrated, finrepresent longitudinal traine members constituting a part of the substructure oi a carbody; A2, a transverse plate connecting said members at their lower portions; A3', a plate forming a covering above the space between the members A, A; lira pair ot front stops Jlor the draitgear, said stops being secured to the inner sides ot the longitudinal nienr bers A, A5, a pair oi" rear stops Afor the draft-gear, similarly secured to the menibers A, g B, B', iront and rear follower plates, or stops, which engage, respectively,

l the front and rear stops; C, the improved draft-gear interposed betiveenthe follower Specification of Letters Patent.

-tion shoe preferably comprises Serial No. 375,5;72.

plates; D, a longitudinal yoke embracing the follower' plates and the interposed draftgeur; and D. a draw-bar equipped near its rear end with a transverse pin D2 which extends freely through a slot l' in the furcated front end of the yoke and works freely 1n guide-slots 2 with which the frame menibers A, A are provided.

The construction providing for the mounting of the draft-gear and theconnection thereof with the draw-bar may be anv desired construction. .ln the form showii. the yoke D is provided at its front end with fui-cations la through which the transvci e slot l entends.v The :voire D has an. longitudinal member L, a lower longitu. member lc. a Jiront wall or shouldcrl whirl. engages the iront toll-inver, and a f or shoulder le which engages therear follower. Y

i The drat't gear (l comprises an elongated inner spring casing C; an elongated outer casing C2 which freely receives the inner 'using telcscopically; a iilurality of elongated segmental friction shoes C inteitposed between the two casing's; a heavv service spring C1 within the iniier casing and adaptV- ed to exert force tending to nuove the inner casing in one ,direction and the friction shoes in the opposite direction.; and a smaller restoration spring C5 interposed `between the trout end oi the inner casing C and therear ,end ofthe outer casing C2. ln the illustration given,

casing ric bers mentioned are of circular crosser .lhc inner casing member C prelerahlv comprises a cvlindrical n'icinbcr which, in 'the illustration given, tapers very7 grudnallv from the iront end to the rear end. the rear end being of a little less diameter'tha the iront end; and said member Gf is provided at its front end with an inturned 'llange or wall 3 which aii'ords a shoulder for the coil springs C4 and (.f" to bear against.

The outer casing C2 preferably comprise a strong cast steel cylinder provided at it rear end with an inturned flange or well which bears against the 'follower ll. E segmental shoes which are interposed tween the two Acylinders are sil i as s in number. They substantially lill the sn ce between the two cylinders, but are separa at their edges by small spaces 5. Each tricsegmental member esten-.flingfapproriinetely elongated A/the full length ol the cylinders. Tach ot' 'Wedges The wedges 6 are provided with taper surfaces 6 of gradual inclination which engage corresponding taper surfaces with which the annplar recesses 7 are provided. The wedge surfaces preferably form small angles with a horizontal line, the taper being small. Again, the left-hand end of the inner cylinder C' is slightly greater than the right-hand end, as viewed in Fig.- 2, so that the inner cylinderhas a very slight taper. The length of the frictional engage ment between the inner cylinder and vthe shoes under compression, preferably is at least twice the diameter of the inner cylinder.

The shoes C3 are provided at their rear ends with the inturned llanges 8. These Hanges or lips encircle a ring 9 which has an outturned flange 9 which engages the inner surfaces lof the lips. This ring all'ordsa bearing' for the rear endv of the heavy spring C4. Thus, the spring C4' tends to force the shoes rearwardly and hold the draft-gear in its extended condition. i

The small inner vcoil spring C has its front end bearing .against the shoulderv 3 of the inner casing C and has its rear. end extendingr freely thrcughthe ringQ' and engaging the rear end or. wall a or" the outer casing C2. The chiel? function of the spring C5 isto'insure the return ci". the yoke and draw-bar to the extended" position, that is, the draw-bar is normally projected a certain distance in iront ot the end of the car; and it is desirable that the diaw-bar shall be projected automatically immediately follow ing' the boiling operation, in order tha there may be no danger of sticking, witlironse- .quent danger et the draw-bar being suddenly projected when some person stand ing' near the car-coupling.

The draftgear C, as a whole, is interposed between the followers ll and l and within l the yoke D. lWhen the yoke is drawn tor- Acc wardly the follower B 'remainsstationary, of course, while the .follower B 1s caused to exert pressure against the rear end ot the. outer casing member C2. This operates through the wedges 6 to force the segmental shoes inwardly as well as longitudinally, and causes the slices to exert exceedingly strong' gripping action upon the inner cylinder C', which, as stated, tapers gradually. 'l`hus, an exceedingly strong;r resistance is ollered to the forward movement of the outer cylin- Ider and the shoes with relation to the inner cylinder hy the intense friction created.

der and shoes` .at its upper -and lower sides gg aliarse the inner cylinder occurs exactly as in the pulling operation. It may be noted here that in the illustration given the rear end of the draw-bar D abuts against the follower B, and the Jfollower B extends freely through the front end of the yoke D.

lt will be noted that the construction provides for the use of long coil springs; that the construction provides also for the use of friction surfaces of very large area; and

longitudinal series of wedges, which tend to cause the shoe to move in with a parallel movement when the draft-gea r is contracted. lThe improved construction provides for uniform wear of the parts and uniform radial pressure between the shoes and the casingmembers. Substantially uniform radial pressure is exerted between the inner cylinat all points on the outer surface of the inner cylinder.

The outereylinder Cg is shown provided -near its ends with lateral flanges l() which serve as spacing members between said cylinder andthe longitudinal members A., A of the car. The cylinder C2 is also provided with lugs or bearings 11 embraced by the upper and lower members lb and lc of the yoke l). It will be understood'that the device (l, as t whole may be reversed withinthe yoke D. it' desired. lt maybe added that the improved construction utilizes trictional con-` tact substantially throughout the length of the cylinders in the bufnp; and pullingr operations; also that thejconstruction enables long coil springs to curved cross-section of the casings insures 2great strength; and, finally, that the provision of a series of wedges on each segmental shoe and formed integrally therewith tends to simplicity ot construction and increased strength7 and provides for a uni- 't'orm contraction of the shoes upon the :inner cylinder during the contraction of the draft gear under either pulling or buiiing stress.

The foregoing detailed description hasl been given tor clearness ci understandingr only and no unnecessary limitation should be understood therefrom, but the appended claims should be'construed as broadly as perY missible in View of the prior art.

Vthat the construction provides further for a be utilized; also that the What regerd as new and desire to secure b v Leers Patent isn i. n s draft-geni', the coinhinzdion of nn clongned hollow inner springcnsing open aone end and provided wili :in ahutnien it the other end, an elongzi'cd hollow outer casing clescopicsllj,Y receiving' said inner casing, elongaed shoes inteposed hewecn said cnsing's and, each provided wili :i plurality oi" inegrnl wedge-surfaces disposed at intervals throughout iis lengi'h concting with s pluraliy of iniegrzil wedge-surfaces win which one or' said cnsings is provided, said shoes being provided fit one end with iniurned lips, opposite said abutment, and a sprin in said inner casing disposed between said ubuinent and said inurned lips and serving to 'force said shoes and inner casingy in opposite directions.

Q. ln s drufgenr, the combination with 'he sulwsrucnre of a cnr-body provided vviLh sels of stops, :i drow-har und n suitable yoke connected therewith, ol :i mounted in said yoke comprising; un inner spring-casing, an outer casing elescopicnlly receiving the inner casing and provided in te iori;Y ai inervals hronghout is length wish n series of recesses havinginclined walls, n plurality of elongaed friction shoes interposed .between sind casinos, euch shoe having' a series of integral projections corresponding with and received by said recesses, said projections having inclined surfaces co-scing with said firs'i-nuined surfaces, spring `wiichin said inner casingr lnlvintcV o; i. end bearing against one end hereoli and having he opposite end engaging inlips with 'which he opposic ends i' ssd shoes nre provided, sind means Afor rnns'znit'ng pressure 'from fue inner (usingr said so'ps and from the outer oi said stops. the cfunhinii'ion or' :in oliowinner spring-casing having a, gradual external taper and having un nhunient-,at iis hirgeend, an elongated hollow ouer casing clescopicnll,v receivingr said inner casing, elongnil'ed shoes interposed between smid casings and nach provided ivi'h n plurality of integral wedge suriisices disposed at intervals throughouti's length and cofncing with corresponding inregrel vfcilge-si'irfnees wih which he o one sei of' device -witli outer casing is proviiflcd internally and erich provided, also at the end rcinoe :from said abutment .vitl un inurned lip, and u spring in said inne5 easing confined heween sind ahuinent and said inturned lips und serving; to *force said shoes und inner raising' in oppo site directions.

4l, In o. drnftgenr, he eon'ihinnion of nn elonffned hollow inner springezisin video :is one en l with :in nhutinen euch provided wi'h u series of eviernir tegrul projecions correspondingj wir-h recesses :ind having wedge-surfaces conci;- ing?r wili said first-named wedge-surfaces :ind euch provided wih :an nhunient n the end remote from said first-named nbunien. and :i spring in said inner casing confined hetween the nhuiment nl the inner raising und the nhntnicns ol' said shoes.

ln :i draft-gear, the conihir the substructnic of u cnr-hod. pr iiiied wih ses oi stops. n draw-har and s. suitnhl nipcred (.'jvlindricul inner ,spring-casing open.

et the snndl end and irovided with un cnd vnll :it the large en( :1n elongoed cvlin drical outer (':isii'ng ielrscopirnlly receiving said inner casingr sind provided wih n closed end and having injcrioiljY und suhsnninlly hroughout is lenn'h n s 1: of nnnuinr recesses provided wiiih wedg'i- :i oliiA rzilitjv of trnnsverscly our ;rnnniiil i tion shoes inirfrposed heivreef .nid c: inders und hnvinginturned lips :1i

their ends more from lhe end wnn of lie inner each ol" seid sl'ioesheingf provided on i vex sur ce with :i series of segun` jecions having wedgefsiunrrs rosaid irs-nzuned ivcdge-surfze' heavy coil spring interposed hrwiai. cud wall of snid inner casing und l'hc inturned lips o' sind shoes. nud :i smaller oil spring inerposed hiwcen thc und wel m. oi smid inner casing and hc closed end o sind outer casing. 

